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Copyright of Acta Scientiarum Naturalium Universitatis Sunyatseni / Zhongshan Daxue Xuebao is the property of Sun-Yat-Sen University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dissolved oxygen content is an important factor affecting eel culture. To improve the prediction accuracy of dissolved oxygen concentration in eel ponds, this paper proposes a model for predicting dissolved oxygen concentration in eel ponds based on the sparrow search algorithm (SSA) and long short-term memory neural network ( LSTM), after optimizing the hyperparameters of LSTM model using SSA algorithm, the dissolved oxygen in circulating water eel culture ponds was predicted. The results showed that the prediction accuracy of SSA-LSTM model was 96. 77%, which was 2. 09%, 3. 34% and 0. 55% higher than the control models LSTM, GRU and PSO-LSTM, respectively. The other indicators of this model, EMSE, EMAE and ERMSE, were 0. 67, 0. 53, and 0. 81, respectively, which also showed significant decreases compared with the control model. The results indicate that the SSA-LSTM model has good accuracy and robustness in predicting dissolved oxygen concentration in eel ponds, which can provide a basis for accurate regulation of water quality parameters in eel culture. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Light Industry Machinery is the property of Light Industry Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Developing a rapid and sensitive analytical method based on ultrafast liquid chromatography-tandem mass spectrometry (UFLC-MS/MS) with solid-phase extraction (SPE) for the simultaneous determination of nine estrogens (dienestrol, diethylstilbestrol, estrone, hexestrol, 17-alpha-estradiol, 17-beta-estradiol, estriol, 17alpha-ethinylestradiol and estradiol valerate) in eel., Methods: After the sample was extracted by acetonitrile and cleaned by Waters Oasis HLB solid-phase extraction cartridge, the UFLC separation was performed on a Shim-pack XR-ODS II column (100 mm x 2.0 mm, 2.2 microm) with a linear gradient elution program of methanol solution containing 0.04% ammonia (v/v) and 0.04% ammonia aqueous solution (v/v) as the mobile phase. Electrospray ionization was applied and operated in the negative multiple reaction monitoring (MRM) mode. The quantitation was used by isotope internal standard dilution technique., Results: The results showed that the limits of quantitation (LOQs, S/N(10) were in the range of 0.07-0.4 microg/kg, the calibration curves were in good linearities for the nine analytes in the range of 0.5-50.0 microg/L with the correlative coefficients (r2) more than 0.998, the recoveries were between 81.0% and 110.0% with the relative standard deviations (RSDs) of 1.92%-8.24%. Additional, the mass spectra characterization of the nine estrogens was discussed and the fragmentation pathways were speculated., Conclusion: The developed method is rapid, sensitive, specific and reproducible, and adapts not only to the simultaneous determination of the nine trace estrogens including the epimer of 17-alpha-estradiol and 17-beta-estradiol but also to the identified detection in other fish tissues.

In order to obtain quality control samples for the analysis of flumequine residue in eel which are consistent with real detection samples, minced eel was prepared as natural matrix standard samples containing flumequine. The results showed that through the administration of drug application and appropriate time of sample acquisition, the natural positive matrix containing the expected levels (5-10 microg/kg) of flumequine and the representative of actual samples at the original state could be obtained. The uniformity of the material was ensured by homogenizing and paddle type blending. The irradiation of Co60-gamma rays at 12 kGy and the packaging material could prevent the degradation of the minced samples at ambient temperature and facilitate the inter-laboratory transfer in any season.

A multiresidue analytical method was developed for the determination of 191 pesticides in fugu, eel and prawn using gas chromatography-mass spectrometry (GC-MS). The samples were extracted with ethyl acetate and cyclohexane (1:1, v/v), and cleaned-up by gel permeation chromatography (GPC). The GPC eluant collected from 26 min to 44 min was concentrated to 1 mL, then analyzed using GC-MS. A DB-1701 column was used for the separation. The MS detection was performed in selected ion monitoring mode. The recoveries were determined at the two spiked levels of I LOQ and 4 LOQ (LOQ: limit of quantification). The overall recoveries were from 50.2% to 120%, and in which the recoveries of 89.5% pesticides were from 70% to 120%. The relative standard deviations (RSDs) of the recoveries were from 0.6% to 21.6%. The calibration curves of all pesticides showed good linearities in the respective ranges with the correlation coefficient above 0.97. The limits of detection and the limits of quantification were 0.002-0.3 mg/kg and 0.007-1.2 mg/kg, respectively. The sensitivity and accuracy of the method met the requirements of the multiple pesticide residues. This method was applicable to determine 191 multiple pesticide residues in fugu, eel, prawn and other fishes.

In the present paper, the synchronous fluorimetric spectra of norfloxacin, lomefloxacin chlorhydric acid, and levofloxacin lactate with deltalambda = 190 nm in a B-R buffer medium of pH 2.87 were measured, and the partial least squares (PLS) method was applied to the quantitative resolution of the seriously overlapped fluorimetric spectra of these compounds. The linear ranges for norfloxacin, lomefloxacin chlorhydric acid, and levofloxacin lactate are 0.016-0.40 microg x mL(-1), 0.01-0.336 microg x mL(-1) and 0.01-0.336 microg x mL(-1), respectively. The limits of detection are 0.012 6 microg x mL(-1) for norfloxacin, 0.006 microg x mL(-1) for lomefloxacin chlorhydric acid, and 0.007 2 microg x mL(-1) for levofloxacin lactate. The analytical results by PLS were compared with principal components regression (PCR) and classical least squares (CLS), and this method was applied to the determination of these three compounds in eel samples with satisfactory results.

A method for rapid determination of oxolinic acid residues in baked eels and fresh eels by high performance liquid chromatography without derivatization was studied. The samples were triturated, and extracted with methylene dichloride. The extracted solutions were evaporated to dryness, and then was dissolved by using the mobil phase. The solutions were cleaned-up by partition with n-hexane before analysis. The components were analysed on a Nova-Pak C18 column (150 mm x 3.9 mm i.d., 5 microm), with methanol-diluted phosphoric acid (pH 2.5) (40:60, V/V) as the mobile phose at a flow rate of 0.8 mL/min and detected by a fluorescence detector at the excitation wavelength (lambdaex) 254 nm and the emission wavelength (lambdaem) 375 nm. The detection limit was 0.01 mg/kg (S/N = 3). The recoveries were over 80 %, and the relative standard deviations (RSDs) were less than 3.8%.

The effects of eel oil capsule on memory obstruction of mice were observed in step-down test, step-through test, Y-maze test and Japanese labyrinth test. The results indicated that the eel oil capsule treating group with dosages of 0.234, 0.702 and 2.106 g/kg markedly enhance the acquirement, strengthing and reappearance of memory, having the functions of improving brain memory hurt by Anisodine.

Step-down test, step-through test and water maze in mice were used to observe the effect of eel oil capsule on mice memory. The results indicated that during the administration period (30 days), the eel oil capsule treating groups with dosages of 0.129, 0.387, and 1.161 g/kg obviously improved the learning and memory abilities. Compared with the control test, the eel oil capsule promoted the memory and smart.